Method for preparing and chemically boiling off the gum of retted flax to allow its ready spinning



Jan. 7, 1964 ARNAUD T 3,116,968

METHOD FOR PREPARING AND CHEMICALLY BOILING OFF THE GUM OF RETTED FLAXTO ALLOW ITS READY SPINNING Filed May 25. 1960 2 Sheets-Sheet 1 PECTOSEAND GUM REMOVAL TREATMENT E Flax Fibre WATER TEMf INITIALLYSO c RAISED//v 30 MIN DISCOLOR/NG C0 Na FTBRES LEFT BA TH 'IN BATH FOR 30 FURTHERWafer a/- 90C MINUTES SoffSoop Li uid Scab Silicate BLEACH/N6 HijmgenPemm, For abour 1 1/2 hours TEMP 40C OIL/N6 Form/R Acid 30min BATHTrammo/ B WASH DRAIN DRYING INVENTOR. i. H9 Lam Wm ET RL 1964 ARNAUDETAL ,116, 68

METHOD FOR PREPARING AND CHEMICALLY BOILING OFF THE GUM 0F RETTED FLAXTO ALLOW ITS READY SPINNING Filed May 25, 1960 2 Sheets-Sheet 2 DRYTREATMENT F LAX HBRE WATER Tegwpemrure DISCOLOR/NG CO NaH 50 C CO3 N02lmmerse fibre for 4 hours RINS/NG Temperature BATH 45 C Immerse fibrefor! hour F A id nd 0 l L l N 6 arm IC C G TemPemfu/e Tram/'no/ B C BATHImmerse for 1 hour WASH in Sofiwafer DRAIN DRYING Z INVENTOR Lou'sHRNMAD United States Patent Ofitice ddlhfiitid Patented Jan. 7, 19%?4 311d 968 METHSD F8101 PREPisRlf lG AND CHEMICALLY BOILING (EFF TiEiE GUMF RETTED FLAX TO ALLOW ETS READY SPWNTNG This invention relates tomethods for preparing retted fibres.

An object of the invention is to provide an improved method forpreparing retted flax and removing chemically its gum, said method beingeffected with or without a final bleaching operation according to thefinal application intended for the ultimate thread.

Textile fiax fibres are well known, both as to their origin and as tothe various treatments and applications thereof. With respect to saidtreatments, it is desired to stress the fact that flax fibres intendedfor treatment in spinning frames should be previously freed of dust andreduced cross-sectionally so that they may be used, after chemicaltreatment, on a selected spinning frame. This corresponds primarily to aphysical preparation of the material, which should be effected in a verycareful manner.

The fibres are then treated chemically in accordance with a method whichforms the object of the invention, the process differing according towhether it is desired to retain the appearance, feel and colour of flax,which requires a dry treatment, or whether it is desired to remove fromthe fibres the pectoses and the gums binding the fibrillae to providethe fibres with suitable elastic and Water-absorbing properties.

The accompanying drawing diagrammatically illustrates both of themethods according to the invention.

Ne will describe a method for the dry treatment of the retted flaxfibres, with a view to making said fibres retain their natural structureand original color, after they have been retted in a bacterial bath.

Generally speaking, and without this forming a limitation of ourinvention, we use for each 100 kgs. of fibres to be treated, a containeror a vat of a commercial type, which may be readily heated and which isequipped with a steam input, with an input of running water and alsowith means for controlling the draining or exhaust of the vat. Thelatter may have a capacity of about 2,000 litres. The weight ratiobetween the material and the bath is thus equal to The method referredto is as follows:

(1) Treatment of the fibres in a discolouring bath constituted by softwater.

Said bath is obtained by dissolving in water 1 gr. per litre of sodabicarbonate CO NaH and 3 grs. per litre of neutral soda carbonate CO NaThe bath is heated to a temperature of 50 C. and the fibres are thenimmersed for 4 hours under intermittent stirring conditions.

(11) Treatment of the fibres in a rinsing bath.

The fibres are immersed in water at a temperature of 45 C. for 1 hourunder intermittent stirring conditions.

(Til) Treatment in an oiling bath.

We prepare a solution at C. of 40 centilitres of formic acid for each100 kgs. of material to be treated and of 0.5 gr. of a commerciallyavailable soluble oiling oil of paraffin oil base or likeself-emulsifying oiling products.

This bath is continued for 1 hour under intermittent stirringconditions.

(IV) Two Washing operations are then performed in soft water.

(V) The fibres are subjected to a draining after said washingoperations.

(VI) We proceed finally to a drying at a temperature of 60 C. at amaximum or in the open. When drying at a raised temperature, the lattershould not exceed the figure given, so as to avoid any possible damageto the fibres.

It is then possible, if desired, to open the fibres over a beater.

We will now describe a second method adapted to produce a treatmentremoving the gum, followed by a leaching or otherwise, with a view toobtaining fibres which are entirely devoid of gums binding together thefibrillae. Such fibres are used in various spinning frames, either aloneor in admixture with other vegetable, animal, artificial and/ orsynthetic fibres.

According to said second method, we may resort to a Vat of a commercialtype having the above-disclosed appertenances and the capacity of which,in particular, provides a bath weighing twenty times the materialtreated therein. This second modus operandi is then as follows:

(1) Treatment of the fibres in a discoloring gum-removing bathconstituted by soft water.

There is introduced into said bath constituted by running water, thetemperature of which is 50 C. at the start, 1 gr. per litre ofbicarbonate of soda CO Na and liquid caustic soda NaOH at 30 B. at therate of 10 litres per 1,000 litres of water. The temperature is raisedduring a period of 30 minutes up to C. and the fibres are left in thebath during 30 further minutes at said temperature, after which the bathis drained off.

(ii) The fibres are treated in a bleaching bath and to this end, thereis introduced into the same vat, without any rinsing, water heated to atemperature of 90 C. We then mix together 1 kg. of soft soap for each1,000 litres of water with 1.5 litres of liquid soda silicate, for each1,000 litres of water and we added peroxide of hydrogen at 130 volumesat the moment of the boiling at the rate of 5 litres of peroxide ofhydrogen for every 1,000 litres of water. In case of overflow, the levelof the bath with the material immersed therein is maintained at thedesired level through the incorporation of water at the same temperatureof 80 C. The duration of the actual bleaching treatment is about 1 /2hours.

(III) Treatment in the oiling bath.

The fibres are rinsed at 40 C. for 30 minutes with a mixture of 10centilitres of formic acid and 1 litre of the aforesaid oiling product,for each kgs. of flax material to be treated.

(IV) We proceed with two washing operations with soft water.

(V) The fibres are subjected to a draining after the washing operations.

(VI) Lastly, the drying is effected at a temperature of 60 C. at amaximum or in the open.

It is also advantageous, if required, to finally open the material on asuitable beater.

According to a modification, the first treating operation of the fibresin a discolouring and gum-removing bath constituted by soft water, maybe effected in running water having at the start a temperature of 50 C.and containing 1 gr. of bicarbonate of soda (CO T-1N2.) at the rate or 1gr. per litre and liquid caustic soda at 36 B. at the rate of 10 litresper 1,000 litres of water.

Furthermore, within the scope of our invention as defined by theaccompanying claims, the method described and its modifications areapplicable to green flax obtained directly from the ripe crop when theseeds may be separated from the stalks.

Before treating such green flax according to our invention, it should besubjected to the conventional cleaning i.e. the seeds should beseparated from the stalks, after which a conventional stripping isperformed to separate the straw from the actual fibres. Said treatmentis operated in a suitable medium. The fibres are then subdividedlongitudinally according to their intended application, after which theyare opened by any machine which may serve for said purpose.

The fibres appear then in the form of flax waste, or else, as acontinuous material in the shape of an untwisted cord and it issubjected to any of the above-mentioned treatments.

Under similar conditions, the method according to our invention isapplicable to China grass and to hemp, after said materials have beensuitably treated to form scurffree strips.

What we claim is:

1. A method for preparing retted fibres comprising immersing about onepart of said fibres in about twenty parts of a discoloring bath at atemperature of about 50 C. for about four hours, said bath beingprepared by dissolving soda bicarbonate and neutral soda carbonate insoft water, rinsing said fibres in water at about 45 C. for about anhour with stirring, immersing said fibres in an oil bath prepared bydissolving a soluble oiling oil in formic acid, draining the oiling bathfrom the fibres, and drying the fibres.

2. A method for preparing retted fibres comprising immersing about onepart of said fibres in about twenty parts of a discoloring bath at aninitial temperature of about C., the bath being prepared by dissolvingbicarbonate of soda and liquid caustic soda in soft water, raising thetemperature of the bath to about C. in about thirty minutes, leaving thefibres in said bath for about another thirty minutes, draining oif saidbath, treating the fibres in a bleaching bath consisting of a mixture ofsoft soap and liquid soda silicate to which is added peroxide ofhydrogen when the mixture is boiled, treating the fibres in an oilingbath consisting of soluble oiling oil dissolved in formic acid, andwashing, draining and drying the fibres.

3. A method of preparing retted fibres comprising treating one part ofsaid fibres in about twenty parts of a discoloring bath at a temperatureof at least 50 C. and then treating the fibres in an oiling bathprepared by dissolving a soluble oiling oil in formic acid.

References Cited in the file of this patent UNITED STATES PATENTS

1. A METHOD FOR PREPARING RETTED FIBRES COMPRISING IMMERSING ABOUT ONEPART OF SAID FIBRES IN ABOUT TWENTY PARTS OF A DISCOLORING BATH AT ATEMPERATURE OF ABOUT 50*C. FOR ABOUT FOUR HOURS, SAID BATH BEINGPREPARED BY DISSOLVING SODA BICARBONATE AND NEUTRAL SODA CARBONATE INSOFT WATER, RINSING SAID FIBRES IN WATER OF ABOUT 45*C. FOR ABOUT ANHOUR WITH STIRRING, IMMERSING SAID FIBRES IN AN OIL BATH PREPARED BYDISSOLVING A SOLUBLE OILING OIL IN FORMIC ACID, DRAINING THE OILING BATHFROM THE FIBRES, AND DRYING THE FIBRES.